\begin{tikzpicture}[>=Stealth, scale=0.8]
    \node at (0, 0) {点 $Z(a, b)$};
    \node at (6, 0) {向量 $\overrightarrow{OZ}$};
    \node at (3, 3) {复数 $Z = a + b\,i$};

    \draw [thick, <->] (1.2, 0) -- (5, 0);
    \node at (3, 0.5) {一一对应};

    \draw [thick, <->] (0.5, 0.4) -- (2.5, 2.5);
    \node [rotate=45] at (1, 1.5) {一一对应};

    \draw [thick, <->] (3.5, 2.5) -- (5.5, 0.4);
    \node [rotate=-45] at (5, 1.5) {一一对应};
\end{tikzpicture}
